cd player whine!

[kartman24]

strange one here, i was stuck in traffic for several hours the other evening (M1 crash), and the car behaved perfectly with no sign of overheating, but as the time went by i noticed the cd player (6cd auto changer in boot) had developed a whining noise that goes up and down with the engine revs of the car! i`ve had this on car radio`s in the past, but never on a cd player. any ideas what`s caused it and how i can cure it? thanks----martin